Issues with fputs

I'm doing and small exercise where I choose a file and I want the content of the file in reverse, I got problems in the last loop, this is the error I got Process returned -1073741819 (0xC0000005) execution time : 5.427 s

Example:

File1:

 Line1
 Line2
 Line3

File2:

 Line3
 Line2
 Line1

This is my code

#define MAXCHAR 1000
int main()
{
    FILE *fptr1, *fptr2;
    char filename[MAXCHAR];
    int i=0;
    char *lines[4];

    printf("Enter the filename to open for reading \n");
    scanf("%s", filename);

    fptr1 = fopen(filename, "r");
    if (fptr1 == NULL){
        printf("Cannot open file %s \n", filename);
        exit(0);
    }

    for(i=0;fgets(filename, MAXCHAR, fptr1) != NULL; i++){
        lines[i] = filename;
        //printf("%s", lines[i]);
    }

    //FILE 2
    printf("\n Enter the filename to open for writing \n");
    scanf("%s", filename);

    fptr2 = fopen(filename, "w");
    if (fptr2 == NULL)
    {
        printf("Cannot open file %s \n", filename);
        exit(0);
    }

    for(i = 4; i > 0;i--){
        fputs(lines[i],fptr2);
    }


    fclose(fptr1);
    fclose(fptr2);
    return 0;
}